Circbord™ prototyping boards with printed circuitry cover a wide range of design requirements — without the expense of edge connectors. All boards have provisions for I/O connectors. Several circuit patterns are available. All bus and pad surfaces are solder coated for user convenience. Holes are 0.042" diameter, hole patterns are based on 0.1" grids. Sockets and pins, terminals, tools and accessories are available separately.Pad-per-hole., plated-thru holes, 0.080 ” diameter, isolated solder pad around each hole on both sides.